What does the number 4 represent in 4nh3

In , the 4 has been the coefficient of the compound and represents the number of molecules of ammonia.

has been a compound of nitrogen and hydrogen. The compound has been a covalent compound, formed by the sharing of electrons in between nitrogen and hydrogen.

The compound has been consisted of 1 nitrogen atom and 3 hydrogen atoms. The hydrogen atoms bonding results in the completion of the octet of the nitrogen and provides stability to the compound.

While writing the chemical equation, the coefficient of the compound has been describing the number of molecules present in the reaction. In , the 4 has been the coefficient of the compound and represents the number of molecules of ammonia.

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answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).